Journal of Polymer Science. Part B, Polymer Physics最新文献_第2页

Aggregation and disaggregation of Aeromonas gum in an aqueous solution under different conditions 不同条件下胶气单胞菌在水溶液中的聚集和分解

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Journal of Polymer Science. Part B, Polymer Physics Pub Date : 2000-10-15 DOI: 10.1002/1099-0488(20001015)38:20<2644::AID-POLB40>3.0.CO;2-#

Xiaojuan Xu, Lina Zhang

{"title":"Aggregation and disaggregation of Aeromonas gum in an aqueous solution under different conditions","authors":"Xiaojuan Xu, Lina Zhang","doi":"10.1002/1099-0488(20001015)38:20<2644::AID-POLB40>3.0.CO;2-#","DOIUrl":"https://doi.org/10.1002/1099-0488(20001015)38:20<2644::AID-POLB40>3.0.CO;2-#","url":null,"abstract":"The aggregation and disaggregation ofAeromonas (A) gum, an acidic heteropolysaccharide, were investigated by viscometry, a fluorescent probe, and gel permeation chromatography combined with laser light scattering techniques in aqueous solutions containing desired NaCl at different temperatures. The A gum had a strong tendency of aggregation and high viscosity in the aqueous solutions. The weight-average molecular weight, z-average radius of gyration, weight-average molar number (w ag ), and apparent aggregation number (N ap ) of the aggregates were investigated and discussed. The results indicated that there were three regions that corresponded to three kinds of aggregates and two transition temperatures at about 35 and 75 °C in the disaggregation course. When the temperature was higher than 75 °C, the w ag hardly changed, and there was still a certain amount of aggregates even at 100 °C, indicating that the aggregates were difficult to disrupt completely. Moreover, the aggregation was thermally irreversible. Decreasing polysaccharide concentration reduced the content of the aggregate. However, N ap remained constant around 20, independent of the polysaccharide concentration in a 0.5 M NaCl aqueous solution at 25 °C. At a salt concentration greater than or equal to 0.05 M, the aggregation was almost independent of the salt concentration used here.","PeriodicalId":16853,"journal":{"name":"Journal of Polymer Science. Part B, Polymer Physics","volume":"19 1","pages":"2644-2651"},"PeriodicalIF":0.0,"publicationDate":"2000-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74189254","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 9

Solid‐state NMR study of cyclo‐olefin copolymer (COC) 环烯烃共聚物(COC)的固体核磁共振研究

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Journal of Polymer Science. Part B, Polymer Physics Pub Date : 2000-10-01 DOI: 10.1002/1099-0488(20001001)38:19<2554::AID-POLB70>3.0.CO;2-#

Wu-Jang Huang, F. Chang, P. P. Chu

引用次数: 8

Interfacial tension and acid‐base approaches to polymer interactions 聚合物相互作用的界面张力和酸碱方法

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Journal of Polymer Science. Part B, Polymer Physics Pub Date : 2000-08-15 DOI: 10.1002/1099-0488(20000815)38:16<2096::AID-POLB30>3.0.CO;2-#

Hua-Ming Liang, R. Xu, B. Favis, H. Schreiber

引用次数: 13

Miscibility, crystallization kinetics, and morphology of poly(?-hydroxybutyrate) and poly(methyl acrylate) blends 聚羟基丁酸酯和聚丙烯酸甲酯共混物的混相、结晶动力学和形貌

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Journal of Polymer Science. Part B, Polymer Physics Pub Date : 2000-07-15 DOI: 10.1002/1099-0488(20000715)38:14<1860::AID-POLB40>3.0.CO;2-#

Y. An, Li-song Dong, Guang-Ke Li, Z. Mo, Zhiliu Feng

{"title":"Miscibility, crystallization kinetics, and morphology of poly(?-hydroxybutyrate) and poly(methyl acrylate) blends","authors":"Y. An, Li-song Dong, Guang-Ke Li, Z. Mo, Zhiliu Feng","doi":"10.1002/1099-0488(20000715)38:14<1860::AID-POLB40>3.0.CO;2-#","DOIUrl":"https://doi.org/10.1002/1099-0488(20000715)38:14<1860::AID-POLB40>3.0.CO;2-#","url":null,"abstract":"The miscibility, spherulite growth kinetics, and morphology of binary blends of poly(β-hydroxybutyrate) (PHB) and poly(methyl acrylate) (PMA) were studied with differential scanning calorimetry, optical microscopy, and small-angle X-ray scattering (SAXS). As the PMA content increases in the blends, the glass-transition temperature and cold-crystallization temperature increase, but the melting point decreases. The interaction parameter between PHB and PMA, obtained from an analysis of the equilibrium-melting-point depression, is −0.074. The presence of an amorphous PMA component results in a reduction in the rate of spherulite growth of PHB. The radial growth rates of spherulites were analyzed with the Lauritzen–Hoffman model. The spherulites of PHB were volume-filled, indicating the inclusion of PMA within the spherulites. The long period obtained from SAXS increases with increased PMA content, implying that the amorphous PMA is entrapped in the interlamellar region of PHB during the crystallization process of PHB. All the results presented show that PHB and PMA are miscible in the melt. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1860–1867, 2000","PeriodicalId":16853,"journal":{"name":"Journal of Polymer Science. Part B, Polymer Physics","volume":"64 1","pages":"1860-1867"},"PeriodicalIF":0.0,"publicationDate":"2000-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83142634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 23

Heat capacity and thermodynamic functions of crystalline poly(p-phenylenebenzobisoxazole), the synthetic polymer with the highest Young's modulus † 杨氏模量†最高的合成聚合物聚对苯基苯并苯异恶唑晶体的热容量和热力学函数

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Journal of Polymer Science. Part B, Polymer Physics Pub Date : 2000-06-15 DOI: 10.1002/(SICI)1099-0488(20000615)38:12<1584::AID-POLB20>3.0.CO;2-#

Kazuya Saito, Yasuhiro Takahashi, M. Sorai

引用次数: 4

Transport properties of chitosan membranes: Influence of crosslinking 壳聚糖膜的传输性能:交联的影响

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Journal of Polymer Science. Part B, Polymer Physics Pub Date : 2000-06-01 DOI: 10.1002/(SICI)1099-0488(20000601)38:11<1521::AID-POLB120>3.0.CO;2-#

C. Tual, E. Espuche, M. Escoubes, A. Domard

引用次数: 123

Tack properties of pressure-sensitive adhesives 压敏胶粘剂的粘性特性

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Journal of Polymer Science. Part B, Polymer Physics Pub Date : 2000-05-01 DOI: 10.1002/(SICI)1099-0488(20000501)38:9<1201::AID-POLB12>3.0.CO;2-#

P. Tordjeman, E. Papon, J. Villenave

{"title":"Tack properties of pressure-sensitive adhesives","authors":"P. Tordjeman, E. Papon, J. Villenave","doi":"10.1002/(SICI)1099-0488(20000501)38:9<1201::AID-POLB12>3.0.CO;2-#","DOIUrl":"https://doi.org/10.1002/(SICI)1099-0488(20000501)38:9<1201::AID-POLB12>3.0.CO;2-#","url":null,"abstract":"Relevant experiments are essential to clearly understand the role of various molecular (chemical structure, surface energy, composition), experimental (contact time, contact pressure, temperature) or topological (sample roughness and thickness) parameters, on the tack properties of pressure sensitive adhesives (PSA). The “mechano-optical tack tester” (MOTT) is a novel device that we have developed to provide accurate measurements of both the contact area and the tack strength. The MOTT is designed to apply controlled contact pressures by mean of a quartz prism probe, for determined contact times, onto the surface of PSA samples. The probe is then pulled up at controlled rates while the tearing force (tack strength) and the contact area are plotted versus time. The tack energy is then calculated. Using the MOTT, the influence of various parameters (contact pressure, contact area, sample thickness, …) on the tack properties of PSA samples has been studied. The main result lies in the strong dependence of the tack energy on the sample thickness. This points out that the release energy is close to the interface rather than in the bulk of the PSA films, and is a function of the contact area. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1201–1208, 2000","PeriodicalId":16853,"journal":{"name":"Journal of Polymer Science. Part B, Polymer Physics","volume":"20 1","pages":"1201-1208"},"PeriodicalIF":0.0,"publicationDate":"2000-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86185680","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 48

Tube dilation process in star-branched cis-polyisoprenes 星形支链顺式聚异戊二烯的管状膨胀过程

3区工程技术

Journal of Polymer Science. Part B, Polymer Physics Pub Date : 2000-04-15 DOI: 10.1002/(SICI)1099-0488(20000415)38:8<1024::AID-POLB3>3.0.CO;2-#

H. Watanabe, Yumi Matsumiya, K. Osaki

{"title":"Tube dilation process in star-branched cis-polyisoprenes","authors":"H. Watanabe, Yumi Matsumiya, K. Osaki","doi":"10.1002/(SICI)1099-0488(20000415)38:8<1024::AID-POLB3>3.0.CO;2-#","DOIUrl":"https://doi.org/10.1002/(SICI)1099-0488(20000415)38:8<1024::AID-POLB3>3.0.CO;2-#","url":null,"abstract":"In current tube models for entanglement, the tube representing the topological constraint is considered to move with time. This tube motion results in the constraint release (CR) as well as the dynamic tube dilation (DTD), and an importance of DTD has been argued for entangled star chains. Under these backgrounds, this article examines the validity of the DTD molecular picture for the star chains. For monodisperse star chains having noninverted type-A (parallel) dipoles in respective arms, the normalized viscoelastic and dielectric relaxation functions μ(t) and Φ(t) were found to obey a relationship μ(t) ≅ [Φ(t)]2 if the tube actually dilates in the time scale of the star relaxation. For 6-arm star cis-polyisoprene (PI) chains (having those type-A dipoles), dielectric and viscoelastic measurements were conducted to test this DTD relationship. Both viscoelastic and dielectric properties exhibited characteristic behavior expected from DTD models (assuming the arm retraction in the dilating tube), the exponential increase of the relaxation time and broadening of the relaxation mode distribution with increasing arm molecular weight Ma. However, in the range of Ma examined, Ma ≤ 8Me (Me = entanglement spacing), the above DTD relationship was not valid for a dominant part of the slow relaxation (and the models failed in this sense). Thus, for star chains at least in this range of Ma, the simple DTD picture assuming very rapid CR motion (rapid equilibration in the dilated tube) did not explain the slow relaxation behavior of star chains. This result in turn suggested the importance of the CR motion in this behavior. © 2000 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 38: 1024–1036, 2000","PeriodicalId":16853,"journal":{"name":"Journal of Polymer Science. Part B, Polymer Physics","volume":"69 1","pages":"1024-1036"},"PeriodicalIF":0.0,"publicationDate":"2000-04-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85144585","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 19

Transition metal compatibilization of poly(vinylamine) and poly(ethylene imine) In memory of Olive M. Belfiore on the 88th anniversary of her birth. 聚(乙烯胺)和聚(乙烯亚胺)过渡金属的相容性纪念Olive M. Belfiore诞辰88周年。

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Journal of Polymer Science. Part B, Polymer Physics Pub Date : 2000-02-15 DOI: 10.1002/(SICI)1099-0488(20000215)38:4<552::AID-POLB7>3.3.CO;2-5

L. Belfiore, Erik M. Indra

引用次数: 0

Reversible and irreversible heat capacity of poly(trimethylene terephthalate) analyzed by temperature-modulated differential scanning calorimetry This article is a U.S. Government work and, as such, is in the public domain in the United States of America. 用温度调制差示扫描量热法分析聚对苯二甲酸三甲酯的可逆和不可逆热容量本文是美国政府的一项工作，因此在美利坚合众国属于公共领域。

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Journal of Polymer Science. Part B, Polymer Physics Pub Date : 2000-02-15 DOI: 10.1002/(SICI)1099-0488(20000215)38:4<622::AID-POLB14>3.3.CO;2-L

M. Pyda, B. Wunderlich

引用次数: 4